Organic arsenical compounds



Patented June 30, 1953 ornca ORGANIC ARSENICAL COMPOUNDS Lefixi-niEWitld Urbschat, Koln-Mulheim, Germany, assignor to Farbenfabriken Bayer Aktiengesellschaft, Levcrkusen, Germany, a corporation of Germany "fNe Drawing. Application February 7, 1950, Serial N nasal. In Switzerland February 15, 1949 1 The present inventionrelates to new organic arsenical compounds and to a process of making the same. H The arsenical compounds according to this 1nvention correspond'to the following general formulaI N- -'C'S X wherein X stands for one ofthe radicals:

. I 7R1 AsS -(a and I -AsR,

R1 and R-stand for organic radicals, and R1 may also be hydrogenw Further the radical R1 attached to a nitrogen atom as well as the radicals.

R. attached to an arsenicatom'rnay be united including the hetero: atom to which they are attached to form a heterocyclic ring system; in this ringformation' in addition tonitrogen 'or arsenic other hetero atoms may take part. Asrexamples for R1 may be mentioned hydrogen, alkyl, aryl, aralkyl and polymethyle'ne chains whichmay be interrupted by heteroatoms. These polymeth-' For. this purpose solutions orsuspension of sub-,. stituted arsine oxides or'the corresponding hal-- ides are reacted with the free dithiocarbamici acids or their salts, orarseno-compoundsare fused together with the oxidation products of the dithiocarbamic acids, the thiuram disulfides; the latter reaction may. also be'effected byheating the components in a suitable diluent. Which of these two methods is preferred in a-partic ul'ar case'depends mainly upon the physical properties;

of .the initial materials, "chiefly upon their solu 3 Claims. (Cl. 260-440) bility, but also upon the form in which the initial arsine compounds are most easily obtainable, i. e. whether in their manufacture these initial compounds are most easily obtained as oxides,

halogen compounds or arseno-compounds. Eor the manufacture of the new compounds on a technical scale the'first mentioned method is "best suited using water as solvent; in this case it is. most convenient to react the dithioc'arbamic acids in statu nascendi set free from'the aque ous solutions of their salts in the presence of the solutions or suspensions of the arsinious oxides. The second-method is ofjmore limited applicability, since it dependsupon the stability of the initial compounds in the fusing. By both methods, however, the end products are obtained in good yield and high purity. Y

- As mentioned above in making the new compounds by the first method water is the most suitable solvent; to dissolve the arsine oxides it is sometimes advisable to add a base such as sodium hydroxide. These solutions can now be mixed with aqueous solutions of salts of dithiocarbamicacids and the mixture run into hydrochloric acid. The aqueous solutions of the arsine oxides may. however, first be acidified and then the aqueous,

solutions of salts of dithiocarbamic acids run into them; In" some instances the use of organicsolguished, by an excellent crystallizability; they show no irritating effect and, therefore, may be used for variou technical purposes. particularly suited for the control of plant pests and have the great advantage of possessing not only good insecticidal properties but also good fungicidal properties.

The present invention lowing examples; it is, however, not restricted thereto:

i Eramplefl 318' grams of methyl arsine oxide dissolvedfin mixed with" 6 litres of ,1-.n.-.

5 litres of water are hydrochloric acid. In this solution 860 grams of sodium dimethyl dithiocarbamate dissolved .in.:7- litres of water are, run with vigorous stirring. cooling. Immediately a White precipitate Qishours stirring is.

formed which after, half an suckedloff, washed with water and driedinithe air.

crystals are obtained melting at 144C.

They are,

is illustrated by the r61 By re-dissolving from acetone ;i,.glitteri ng- The above-described reaction takes the following course:

+2HCl s stews.

somerset CHQAS Example 2 168 grams of phenyl arsine oxide are dissolved in 2 litres of n-caustic soda solution under slight heating. Thereafter a solution or" 286 grams of sodium dimethyl dithioca-rbamate dissolved in 3 litres of water is added. The mixture which The above-described reaction takes the following course:

To a solution 80 grams of sodium hydroxide in 1.6 litres of water 170 grams of piperidine are added and 152 gra ns of carbon disulfide dropped in. 'By slightlyheating the reaction is completed.

is only slightly turbid flows, while stirring, as a J thin stream into 4 litres of 1 n-hydrochloric acid diluted with 5 litres of water. After shortly stirring the separated white deposit is sucked ofi; Washed with water and dried in the air. By redissolving from acetone fine needles are obtained which discolor towards 215 C. and melt at 221 C; l

The above-described reaction takes the following course:

s sen ors): 205mm somwnah The reaction between arsenobe'nzene and tetramethyl thiuram disulfide takes place also by boiling the components for a longer period in a suitable diluent, e. g. chloroform.

The same compound is obtained as in Exam- Ewamplee! 183 grams of p-aminophenyl arsine oxide are dissolvedin 2 litres of 1 n-hydrochloric acid and 3'litres of water. With cooling and stirring 286 grains of sodium dimethyl dithiocarbamate dissolved in 5 litres of water are gradually added. After half an hour the milky reaction mixture is diluted with litres of water, and the now flocky deposit is sucked on and washed. From acetone (by the addition of methanol to the filtrate) a white substance is obtained without definite melting point. e

CHgASO 2NaS.C.N

Into the solution ofthe sodium N,N-pentamethylane'dithiocarbamate thus obtained a solution of 106 grams of methyl arsine oxide dissolved in 900 cc. of water-flows with good stirring. Thereafter 1 n-hydrochloric acid is added vuntil the mixture shows a Congo acid reaction. The precipitate is sucked off and redissolved from-alcohol. .White needles are obtained of amelting point of 157 C. v

The above-described reaction takes the 'following course:

By using'174 grams of morpholine instead of piperidine and reacting the sodium salt of the morpholine-4-dithiocarboxylic acid in the same way as described in Example 5, a condensation product is obtained which crystallizes from acetone in'white needles and melts at 174 C.

' 'The above-described reaction takes the following course:

- cereal CHaAsO +2nas.o. o

' \CH2-C: +2116.

HaA

onhor C'Hr-CIE: so):

orifice;

Example? grams of sodium hydroxide dissolved in 1.6.

litres of water, 142 grams of pyrrolidine and 152% grams of carbon disulfide' are reacted to form aj solution containing sodium N,Ntetramethylenedithiocarbamate. By the addition of 106 grams of methyl arsine oxide dissolved in 900 cc. ofwa ter a yellow precipitate is obtained. By the addition of diluted hydrochloric acid until the mixis increased and becomes White.

ExampZeS To a solution of 13.1 grams of diphenylene arsine chloride in 130 cc. of acetone, a solution of grams of sodium dimethyl dithioc arbamate dissolved in 100 cc. of acetone is added, and the mixture is boiled for one hour. After evaporating the solvent, the residue is diluted with water, the precipitate sucked off, washed with water and redissolved from acetone, melting point 142 C.

. The above-described reaction takes the following course:

Example 9 41 grams of sodium phenyl methyl dithiocarbamate are dissolved in 500 cc. of water and added to 10.6 grams of methyl arsine oxide dissolved in 500 cc. of water. Without regard to a deposit formed. hereby, 200 cc. of 1 n-hydrochloric acid are run int the mixture withstirring and inside cooling with ice. The mixture is then stirred for further minutes, the precipitate is sucked off, washed with water and, after drying, re-dissolved from acetone or benzene. White crystals of a melting point of 191 C.

The above-described reaction takes the following course:

/CH3 CHgASO 2NaS.C.N

B S OO S.C.N

Example 10 Into a solution of 44 grams of ammonium dithiocarbamate in 1 litre of water 21.2 grams of methyl arsine oxide dissolved in500 cc. of water are introduced, while adding ice and stirring. Immediately thereafter 400 cc. of 1 n-hydrochloric acid are added. After a short further stirring the white precipitate is isolated and re-dissolved from methanol in the usual manner. White crystalline substance which turns yellow at C. and decomposes from about 138 C. with evolution of gas.

, The above-described reaction takes the following course:

S S. 'hNHa CHaAS 2NH4C1 +1120 5. C.NH:

I claim: v 1. Organic arsenical compounds of the general formula:

N-o s x Rf wherein X stands for a radical selected from the group consisting of:

R1 -AsS-GN i R. and

-As-R R1 stands for a radical of the group consisting of hydrogen, alkyl, aryl, aralkyl, tetramethylene, pentamethylene, and CH2.CH2.O.CH2.CH2, both free valences of these divalent radicals being attached to the nitrogen atom, and R stands for a radical of the group consisting of alkyl, aryl,

aralkyl, and

both free valences of this latter radical being attached to the arsenic atom.

2. The compound of the formula:

being a crystalline substance melting at 144 C.

3. The compound of the formula:

being a crystalline substance melting at 221 C.

EWALD URBSCHAT-.,

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date OTHER REFERENCES Cohen et al.: J. Chem. Soc. (London), 1931, p. 3043 to 3046.

Gazzetta Chimica Italiana, vol. 69, p. 633 to 635, 1939.

' Oechslin May 16, 1933 g 

1. ORGANIC ARSENICAL COMPOUNDS OF THE GENERAL FORMULA: 